A.Sequential; three

B. sequential; two

C. combinational; two

D. combinational; three

E. sequential or combinational; three

9. Make addition of binary numbers: 1001 and 1010. Result is

A. 10011 B.1001 C. 1100 D. 11001 E. 10101

10. To construct 6-bit parallel adder we must use cascade of such full-adders IC s as

A. two 2-bit and one 1-bit B. one 2-bit and one 3-bit C.one 4-bit and one 1-bit

D. five 1-bit E. none of above mentioned, because 5-bit parallel adder IC exists itself

LABORATORY WORK # 6.

BCD ADDER.

Aims: investigate BCD adder operation, make an addition according to the task. Compare the results of the addition with ones, made by theoretical way.

PREPARATION TO LAB WORK.

1. Learn the information about BCD adder and combinational logic.

2. Draw block diagram of a BCD adder with application of Scheme Design System and compare this scheme with a scheme of experiment #6.

3. Answer the questions below in written form.

   1. What is a decimal adder?

   2. What is a BCD adder?

   3. For what purpose do 3 external gates exist in the scheme of BCD adder?

LAB WORK PERFORMANCE.

1. Demonstrate presence of your home preparation for lab work to your instructor.

2. Pass test of 10 questions.

3. Get a permission to begin the work.

4. Mount the scheme of experiment 6 on the breadboard and perform it.

5. Make a conclusion about functionality of the scheme. Compare your results with theoretical ones.

6. Demonstrate your results to your instructor. If your results are correct you may dismount your scheme, if no – find the mistake.

7. Be ready to answer your instructor’s questions in process of work.

8. Complete your work, dismount your schemes, clean your working place.

9. Answer your instructor’s final questions, obtain your mark.

10. Ask your instructor’s permission to leave.

Experiment 6.Realize the circuit on a breadboard. For 2-input AND take 7408, pins 1,2-inputs, pin 3 output. For 2-input OR take 7432, pins 1,2,4,5-inputs, pins 3,6-outputs. Fill in the tables. Connect pin 5 of 7483 to VCC and pin 12 – to GND. Show ONs or OFFs for LEDs. Tasks for addition:

options

Inputs of basic adder

Outputs of basic adder

L1

L2

L3

L4

L5

L6

L7

L8

L9

L10

L11

L12

L13

L14

5+9

7+8

4+3

options	Inputs of correction adder					Outputs of the circuit
	L15	L16	L17	L18	L19	L20	L21	L22	L23
5+9
7+8
4+3

Conclusion: